The supersonic aircraft is designed to accelerate to Mach 7 and Mach
10 - seven to ten times the speed of sound.

I think people haven't even thought about how
to use this technology yet

Joel SpitzNasa project manager

By contrast, a jet fighter plane travels at speeds of Mach 1 to Mach 2, and the Space Shuttle blasts into space at Mach 25.

The unmanned plane will be launched from Edwards Air Force Base in
California and will fly for only about 10 seconds before it crashes into the
Pacific Ocean.

"People have worked their whole careers to see this flight," said Joel
Spitz, the X-43A project manager at NASA's Dryden Flight Research Center.

"We're making aviation history."

The X-43A, or "Hyper-X" was built specifically to test scramjets, or
supersonic ramjets, which burn fuel in air travelling at supersonic speeds. A ramjet uses air
at subsonic speeds.

The plane uses an air-breathing engine, drawing in
oxygen from the atmosphere as it flies, and eliminating the need for heavy, expensive, liquid oxygen tanks. The oxygen combines with hydrogen for
combustion.

Currently, the fastest air-breathing aircraft is the SR-71, which
accelerates to slightly over Mach 3.

The X-43A may be fast, but at this early stage, it needs a push to get
going. To be sure it reaches the necessary speeds, the X-43A will be
attached to a booster rocket and ride piggy back on a B-52 to 24,000 feet.

The test plane will be carried aloft by a B-52 bomber

Once over the Pacific Ocean, the B-52 will drop the rocket, which will then
ignite and accelerate to Mach 7.

The rocket and X-43 will separate, and the
X-43A will enjoy a brief solo flight while engineers run manoeuvres, and test
the plane's air-breathing engine.

Dr Spitz sees unlimited potential with the scramjet.

"We went from Kitty
Hawk to the Moon in 70 years. I think people haven't even thought about how
to use this technology yet."

He suggested that the air-breathing scramjet could revolutionise space
travel, by making passenger and cargo flights into space affordable and
practical.